Evaluation of Biocompatible Photopolymers I: Photoreactivity and Mechanical Properties of Reactive Diluents

Abstract

Important characteristics of bone replacement materials are to support the attachment, growth, and differentiation of osteogenic cells. A second important characteristic of the material is that it can be photopolymerized, which allows the material to be applied to rapid prototyping that enables us to fabricate scaffolds in nearly any shape and structure. In these investigations, reactivity and biocompatibility of different types of commercially available acrylates and photoinitiators were determined. Cell viability was related to the functional groups in the monomers present, e.g., oligoethyleneglycol, urethane‐, hydroxy‐ or carboxy groups. It was found that polymers obtained from acrylates with urethane units, most dialkylacrylamide and especially trimethylolpropane triacrylate gave outstanding biocompatibility. Mechanical testing proved to have significantly better performance (stiffness, strength) than many known thermoplastic biopolymers. Keywords: biocompatibilitybone tissue engineeringcell proliferationmechanical propertiesosteoblastphotopolymerizationrapid prototyping 5 Acknowledgment Samples EPA and UDMA provided by IVOCLAR VIVADENT AG, photoinitiators from Ciba SC, and financial support by the "Austrian Nano Initiative" under contract no. N‐703 is kindly acknowledged.